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hard starting 5.7 l omc io only when warm

mikerevs's Avatar
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07-22-04, 12:42 PM   #1  
hard starting 5.7 l omc io only when warm

I have a 5.7 l 1989 omc IO which starts great when cold or when only running for 10 to 20 minutes. The enginge runs great and the batterys are fully charged. But when I take the boat for a long run, It is hard to start after I shut the engine off. Sometimes it does start while I am cranking and turning the key off. My plugs are new and the engine was coverted to a spitfire electronic system years ago. Please advise.


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Ductulator's Avatar
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07-22-04, 08:17 PM   #2  
I was hopeing that you had a reply, since my 5.7 Merc does the same thing and I have now become used to it. It used to be hard to start cold and keep running but the mechanic wired the choke open and now it starts first time everytime when cold but has the same problem as yours when hot.

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Join Date: Dec 1999
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07-23-04, 07:06 PM   #3  
if you put in the electronic conversion module you may have
problems with the SAM shift assist module.
you can bypass it temporarily by unplugging the small
connecter with the purple wire in it. its behind the distributor.
it sould have three wires and be retained by a wire clip.

the other thing is it might be the starter solenoid robbing voltage.
try that next.

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